pics/public/js/upload_queue.js

216 lines
5.8 KiB
JavaScript

function UploadQueue(options) {
this.queue = options.queue_element;
this.preview_area = options.preview_area;
this.upload_progress = [];
this.upload_url = options.upload_url;
this.submit = options.submit_button;
this.addEvents();
}
UploadQueue.prototype.addEvents = function() {
var that = this;
that.queue.addEventListener('change', function() {
that.showSpinner(that.queue, "Generating previews (not uploading yet!)");
that.clearPreviews();
for (var i = 0; i < that.queue.files.length; i++) {
var callback = (i !== that.queue.files.length - 1) ? null : function() {
that.hideSpinner();
that.submit.disabled = false;
};
if (that.queue.files[0].name.includes(".HEIC")) {
alert('Sorry, the HEIC image format is not supported.\nPlease convert your photos to JPEG before uploading.');
that.hideSpinner();
that.submit.disabled = false;
break;
}
that.addPreviewBoxForQueueSlot(i);
that.addPreviewForFile(that.queue.files[i], i, callback);
};
});
that.submit.addEventListener('click', function(e) {
e.preventDefault();
that.process();
});
this.submit.disabled = true;
};
UploadQueue.prototype.clearPreviews = function() {
this.preview_area.innerHTML = '';
this.submit.disabled = true;
this.current_upload_index = -1;
}
UploadQueue.prototype.addPreviewBoxForQueueSlot = function(index) {
var preview_box = document.createElement('div');
preview_box.id = 'upload_preview_' + index;
this.preview_area.appendChild(preview_box);
};
UploadQueue.prototype.addPreviewForFile = function(file, index, callback) {
if (!file) {
return false;
}
var preview = document.createElement('canvas');
preview.title = file.name;
var preview_box = document.getElementById('upload_preview_' + index);
preview_box.appendChild(preview);
var reader = new FileReader();
var that = this;
reader.addEventListener('load', function() {
var original = document.createElement('img');
original.src = reader.result;
original.addEventListener('load', function() {
// Preparation: make canvas size proportional to the original image.
preview.height = 150;
preview.width = preview.height * (original.width / original.height);
// First pass: resize to 50% on temp canvas.
var temp = document.createElement('canvas'),
tempCtx = temp.getContext('2d');
temp.width = original.width * 0.5;
temp.height = original.height * 0.5;
tempCtx.drawImage(original, 0, 0, temp.width, temp.height);
// Second pass: resize again on temp canvas.
tempCtx.drawImage(temp, 0, 0, temp.width * 0.5, temp.height * 0.5);
// Final pass: resize to desired size on preview canvas.
var context = preview.getContext('2d');
context.drawImage(temp, 0, 0, temp.width * 0.5, temp.height * 0.5,
0, 0, preview.width, preview.height);
if (callback) {
callback();
}
});
}, false);
reader.readAsDataURL(file);
};
UploadQueue.prototype.process = function() {
this.showSpinner(this.submit, "Preparing to upload files...");
if (this.queue.files.length > 0) {
this.submit.disabled = true;
this.nextFile();
}
};
UploadQueue.prototype.nextFile = function() {
var files = this.queue.files;
var i = ++this.current_upload_index;
if (i === files.length) {
this.hideSpinner();
} else {
this.setSpinnerLabel("Uploading file " + (i + 1) + " out of " + files.length);
this.sendFile(files[i], i, function() {
this.nextFile();
});
}
};
UploadQueue.prototype.sendFile = function(file, index, callback) {
// Prepare the request.
var that = this;
var request = new XMLHttpRequest();
request.addEventListener('error', function(event) {
that.updateProgress(index, -1);
});
request.addEventListener('progress', function(event) {
that.updateProgress(index, event.loaded / event.total);
});
request.addEventListener('load', function(event) {
that.updateProgress(index, 1);
if (request.responseText !== null && request.status === 200) {
var obj = JSON.parse(request.responseText);
if (obj.error) {
alert(obj.error);
return;
}
else if (callback) {
callback.call(that, obj);
}
}
});
var data = new FormData();
data.append('uploads', file, file.name);
request.open('POST', this.upload_url, true);
request.send(data);
};
UploadQueue.prototype.addProgressBar = function(index) {
if (index in this.upload_progress) {
return;
}
var progress_container = document.createElement('div');
progress_container.className = 'progress';
var progress = document.createElement('div');
progress_container.appendChild(progress);
var preview_box = document.getElementById('upload_preview_' + index);
preview_box.appendChild(progress_container);
this.upload_progress[index] = progress;
};
UploadQueue.prototype.updateProgress = function(index, progress) {
if (!(index in this.upload_progress)) {
this.addProgressBar(index);
}
var bar = this.upload_progress[index];
if (progress >= 0) {
bar.style.width = Math.ceil(progress * 100) + '%';
} else {
bar.style.width = "";
if (progress === -1) {
bar.className = "error";
}
}
};
UploadQueue.prototype.showSpinner = function(sibling, label) {
if (this.spinner) {
return;
}
this.spinner = document.createElement('div');
this.spinner.className = 'spinner';
sibling.parentNode.appendChild(this.spinner);
if (label) {
this.spinner_label = document.createElement('span');
this.spinner_label.className = 'spinner_label';
this.spinner_label.innerHTML = label;
sibling.parentNode.appendChild(this.spinner_label);
}
};
UploadQueue.prototype.setSpinnerLabel = function(label) {
if (this.spinner_label) {
this.spinner_label.innerHTML = label;
}
}
UploadQueue.prototype.hideSpinner = function() {
if (this.spinner) {
this.spinner.parentNode.removeChild(this.spinner);
this.spinner = null;
}
if (this.spinner_label) {
this.spinner_label.parentNode.removeChild(this.spinner_label);
this.spinner_label = null;
}
};